This invention relates to a rail-mounted mobile system such as a mobile storage system, and more particularly to an ADA-compliant roller guided arrangement for such a system.
A rail-mounted mobile system, such as a mobile storage system, includes one or more movable members supported on a series of spaced apart parallel rails. In a mobile storage application, the movable members are typically in the form of carriages having wheels that are supported on the spaced apart rails. A series of storage units, such as shelves or cabinets, are mounted to each carriage.
Various guide rail arrangements are known for the movement of carriage-mounted storage units. One such example of such an arrangement is shown and described in U.S. Pat. No. 7,165,497 to Gilbert et al. The '497 patent discloses a longitudinally extending track support system and track members for a mobile storage unit. The upper support surface of the track support system has at least one protrusion which projects above and extends longitudinally along the upper surface. A mating recess extends within and along the undersurface of the track member. The recess and protrusion are sized and shaped to provide loose-fit longitudinal engagement of the protrusion within the recess when the track member is laid atop the track support. This permits limited transverse movement of the track member with respect to the track support, reducing susceptibility of the wheels to derailment if a transverse force is applied to the mobile storage unit as it rolls along the track.
Another example of a guide rail arrangement is shown in U.S. Pat. No. 6,948,785 to Frank, which discloses a track system for high-density mobile storage carriages. The system includes parallel tracks for receiving a rail on which the mobile carriages are moved. The tracks are supported on a building floor by multiple transverse leveler channels. The tracks are used to support the wheels of the mobile carriages for efficient rolling along the building floor.
However, the arrangements of the prior art, such as is shown and disclosed in the '497 and '785 patents, suffer from certain disadvantages. Specifically, prior art arrangements require the utilization of guide rails that receive rollers for providing movement of the carriage relative to a support surface such as a floor. Such systems require that openings in the floor for accommodating the rails of the mobile carriage systems are wide enough to receive the rollers on the carriage that are supported on the rails. Under the Americans with Disabilities Act, however, openings in floor surfaces must comply with certain standards, e.g. such openings must be no wider than ½ inch. The aforementioned systems, however, do not meet these guidelines as the floor openings must be large enough to accommodate the rollers, which prevents the use of such rail and roller support systems in many applications.
Accordingly, it is an object of the present invention to provide a guide rail arrangement for a mobile storage system that requires relatively narrow openings in the floor surface, to enable compliance with standards such as the Americans with Disabilities Act. It is a further object of the present invention to provide a narrow opening anti-tip arrangement in which the anti-tip member is carried by a moveable member (i.e., the carriage) to prevent the carriage from tipping during the movement along a drive rail of the system.
In accordance with one aspect of the present invention, a guidance arrangement for a mobile storage system, which includes a series of storage units, has an axial guide mounted within a floor, which defines an upwardly open slot accessible from above a top surface of the floor. The guidance arrangement also includes a drive rail mounted within the floor and extending parallel to the axial guide. A top surface of the drive rail is flush with a top surface of the floor. A roller arrangement is associated with the axial guide, and is located within the upwardly open slot. A rotatable drive wheel is carried by one of the storage units, and is engaged with the top surface of the drive rail. A guide member extends downwardly from the storage unit and into the upwardly open slot, and engages the roller arrangement so as to guide movement of the storage unit as the storage unit is moved along the axial guide by movement of the drive wheel on the drive rail.
In accordance with another aspect, the present invention contemplates a rail system for high density mobile storage assemblies having a number of storage units. The rail system includes an axial guide mounted beneath a floor and defining a first upwardly open slot. A drive rail is mounted beneath the floor parallel to the axial guide, and defines a second upwardly open slot, and is configured to allow for wheels of the storage units to ride thereon. A roller arrangement is mounted within the first upwardly open slot, and is adapted to receive a guide member extending downwardly from the storage units to guide movement of the storage unit at a location spaced from the wheels and the drive rail.
The invention also contemplates a method of guiding movement of a mobile storage unit relative to a floor. The method includes the steps of moving the storage unit by rotation of a drive wheel on a drive rail at a first location, and guiding movement of the storage unit at a second location spaced from the first location, by engaging a downwardly extending guide member associated with the storage unit with a guide arrangement that includes an upwardly open slot through which the guide member extends. The guide arrangement includes spaced apart engagement members that engage the guide member below the floor as the guide member is moved along the upwardly open slot.
Various other features, objects and advantages of the invention will be made apparent from the following description taken together with the drawings.